The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2014
Filed:
Sep. 04, 2012
Akiko Nakada, Kasugai, JP;
Yoji Mori, Komaki, JP;
Naoya Shiroyama, Kasugai, JP;
Minoru Ito, Kasugai, JP;
Akiko Nakada, Kasugai, JP;
Yoji Mori, Komaki, JP;
Naoya Shiroyama, Kasugai, JP;
Minoru Ito, Kasugai, JP;
CKD Corporation, Komaki-shi, JP;
Abstract
A gas flow monitoring system is provided in process gas lines each arranged to supply gas to a predetermined process chamber via a flow control device, the system being configured to measure lowering or rising of gas pressure before and after the flow control device to monitor a flow rate of the flow control device. The system includes a first flow monitoring unit placed upstream of the flow control device in a selected one of the process gas lines, a second flow monitoring unit placed in a discharge passage upstream of the process chamber, and a controller that constantly monitors the flow rate of the flow control device with the first flow monitoring unit and, when the first flow monitoring unit detects the flow-rate abnormality two or more times, commands the second flow monitoring unit to re-verify whether flow-rate abnormality is present or not in the flow control device.